This invention relates to machines and methods for filling and sealing a series of pouches or bags of plastic or other material such as plastic-foil laminates on a continuous basis, and it has particular relation to machines and methods of the type shown in co-owned Weikert U.S. Pat. Nos. 3,813,845 and 4,021,283.
In the apparatus disclosed in those patents, a tube of material is first divided into a series of contiguous bags or pouches sealed from each other along their adjacent sides but interconnecting through a continuous tubular portion which initially forms a common top for all of the bags. The tubular portion of this web is drawn along an elongated filling pipe having a discharge port at one end from which the material with which the bags are to be filled is poured into each successive bag, with this processing line being tilted upwardly so that excess material in one bag will spill over into the adjacent following bag. After each bag is filled, it is sealed across the top and severed from the tubular portion as a separate, filled and sealed package.
The apparatus and methods disclosed in the above patents have been widely used and outstandingly successful in connection with a wide range of materials. In general, however, they have been most successful for packaging essentially liquid materials, e.g. milk, and problems have sometimes developed when the material to be packaged was a suspension of relatively large particulate material, e.g. filling for an apple pie containing chunks of apple. With such materials, pieces of the solid constituents of the mix can accumulate above the seam between contiguous bags in the web, particularly if the mix overflows a bag into the adjacent following bag, and thereafter interfere with proper sealing of the filled bags. The present invention is directed particularly to eliminating the possibility that such accumulation of solids can occur.